New study: APOE4 homozygosity is a new genetic form of Alzheimer’s disease

May 8, 2024
New Alzheimer’s study.

A new study published in Nature Medicine revealed that individuals with the APOE4 homozygosity gene are at a higher risk of developing Alzheimer's disease.

Researchers studied 3,297 individuals for the pathological study and 10,039 for the clinical study, according to the abstract in PubMed.

The findings:

·        “Nearly all APOE4 homozygotes exhibited AD pathology and had significantly higher levels of AD biomarkers from age 55 compared to APOE3 homozygotes.

·        By age 65, nearly all had abnormal amyloid levels in cerebrospinal fluid, and 75% had positive amyloid scans, with the prevalence of these markers increasing with age, indicating near-full penetrance of AD biology in APOE4 homozygotes.

·        The age of symptom onset was earlier in APOE4 homozygotes at 65.1, with a narrower 95% prediction interval than APOE3 homozygotes.

·        The predictability of symptom onset and the sequence of biomarker changes in APOE4 homozygotes mirrored those in autosomal dominant AD and Down syndrome.

·        In the dementia stage, there were no differences in amyloid or tau positron emission tomography across haplotypes, despite earlier clinical and biomarker changes.

·        APOE4 homozygotes represent a genetic form of AD.”

Read the study and abstract here: